2000 grand prix headlights not switching to bright

SOUND LIKE SHORT IN THE TAIL LIGHT BULB SOCKET THAT IS MELTING.REPLACE BULB SOCKET SEE WHAT HAPPENS.

the fog light bulb in the 98 Grand Prix is easy pull pigtail off light turn light from back and it will come out , replace is reverse obviously , but make sure the orientation is correct on housing as there is one tab bigger than the other 2 have to look at it from underneath to see orientation of the bulb housing.

Hi. Since the headlight on the driver side is working then we dont have any problem with the fuse or relay. Check the wiring and the socket of the passenger headlight if it is intact to the bulb. If it is intact, then this could be a headlight problem. Time to replace the passenger headlight.

TEST
remove both bulbs from the lamps but leave them on their wires switch on and see if the bulbs are still different brightness if not they the passenger side lamp housing has damaged mirror is dirty or missalined and needs adjustment. if they are different brightness then this may be a earthing problem.

REPLACE THE FOG LAMP SWITCH DOWN ON THE STEERING COLM. REMOVE THE PROTEC. PANEL UNDER STEERING COLM. AND GENTLY START TO LOWER THE COLM. WATCH OUT FOR THE SHIFT IND. WIRE- REMOVE IT- LOWER COLM. AND HALF WAH DOWN ON THE TOP SIDE IS THE SWITCH FOR THE FOG LAMP CONTROL IF YOU HAVE ALREADY REPLACED THE ELEC. SWITCH - (PUSH BUTTON OR ROCKER STYLE ).IN THE DASH. IF - - LIGHTS AREON AND THE FOG LAMPS ARE TURNED ON AND THE HEAD LIGHT GO OUT OR WONT CHANGE FROM DIM TO BRIGHT REPLACE HIGH/LOW SWITCH ON COLM. SAME PROCEDURE AS FOG CONTOL SWITCH.

Most fog lights turn off when you put your brights on. Check their operation in normal mode first, if they turn off when you turn your brights on... this is normal.

To disable this you need the wiring diagram for your car, you will have to cut 1 wire to be able to have all your lights on at the same time.

SYLVANIA H7 SILVERSTAR HIGH PERFORMANCE HALOGEN HEADLIGHT BULB -- 55 Watts, Single C-8 filament for use as either high beam or low beam; 100 percent legal halogen headlight bulbs; Features the whitest and brightest light colour similar to daylight for safer night driving; Meets all US FMVSS 108 and Canadian CMVSS 108 requirements. Fits Driver or Passenger Side Driver or Passenger Side Fits the following vehicle/s
2004 Audi S4 Base 8 Cyl 4.2L 2004: Base; 8 Cyl 4.2L RAMPAGE FOG LIGHT, BLACK METAL HOUSING, With round clear lens; Includes 100-Watt H3 halogen bulb, one lamp and a single bolt mounting system; Provides better illumination Fog Light

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  Fits the following vehicle/s: 2004 Audi S4 Base 8 Cyl 4.2L 2004: Base; 8 Cyl 4.2L;

Recheck the bulb number. This happens when the wrong bulb number is installed. Otherwise it could be a bad headlight ground.

Check at the headlight sockets for a bad ground.

I had the same problem. My mechanic checked it for me. He found that the wiring connection on the back of the switch had worked itself off over time. He connected the wiring and it works perfectly.